Partial support is requested for the annual meeting of the Gerontological Society of America (GSA) at the Hilton Square in San Francisco, California, November 22-26, 1991. This grant will partially fund a symposium for the Biological Sciences Section of the GSA. We anticipate that about 1500 biologists and physicians will attend (the annual meeting of the American Geriatric Society will be held immediately before this meeting) and that overall attendance will be about 3500. The Gerontological Society of America is the largest professional organization of aging researchers in the US, with approximately 7,000 members organized into four different sections representing the major academic divisions of the membership. The first three listed purposes for the existence of the GSA ( ... "to promote the scientific study of aging..., to stimulate communications.... and to expand education in aging") are fulfilled largely through the annual meetings. The overall theme of the meeting is "New Knowledge: Key to Meeting the Challenge of Aging"; that of the Biological Sciences component, "The Molecular Basis of the Processes of Aging and Senescence," is consistent with this theme. Biological research in aging is currently proceeding at a pace and at a level of sophistication unprecedented in Its history. This increased pace of discovery is accompanied by ever more specialized methodologies and necessary background information; consequently, the annual meetings play an increasingly important role in providing a venue for communication between investigators with disparate areas of expertise. Biotechnology has transformed the biological sciences and over the last five years biological aging research has firmly joined the molecular revolution. in keeping with these changes, the meeting will concentrate on five topics for which I seek support: (1) Functional Aging of the Immune System, (2) Second Messengers in Aging of the Central Nervous System, (3) Cellular Senescence and Replicative Arrest, (4) DNA Repair, Protein Degradation, and oxidative Processes, and (5) Transcriptional changes during Aging. These topics all represent areas in which dramatic advances have been made in the last few years.